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SoCal Burning

Scenes from Southern California's wildfire siege

SoCal Burning

Scenes from Southern California's wildfire siege

Southern California is no stranger to wildfires, but even by historical standards, the events of early December 2017 stand out. The dreaded Santa Ana winds, which transport warm, dry air from inland toward the coast, have been unceasing. The air is dry enough to ignite any vegetation exposed to a spark, be it a downed power line, carelessly-discarded cigarette, or an arsonist's can of gasoline.

Through December 7, wildfires had burned more than 100,000 acres in the greater Los Angeles area alone, with more than 200,000 people evacuated from erratic flames fanned by 50 to 80-mile-per-hour winds. The Thomas Fire, in Ventura, about 60 miles northwest of downtown L.A., has proven to be the biggest blaze so far, burning at least 132,000 acres. This makes it one of California's top 20 wildfires on record, according to Cal Fire.

The weather conditions have been too difficult for firefighters to gain the upper hand against many of the wildfires, with the combination of the winds, lack of significant rain for at least 8 months, and some of the driest air ever measured in this part of California. In San Diego, the National Weather Service found relative humidity levels well below 10 percent on Thursday, with tinderbox dry air draped across the entire West Coast.

Homes burn as an firefighters pull hosea to keep flames from advancing to adjacent homes at Rancho Monserate Country Club on December 7.

Gina Ferazzi/Los Angeles Times/Getty Image

Edward Aguilar runs through flames from the Thomas Fire to save his cats at his mobile home along Highway 33 in Casita Springs in Ventura County on December 5.

Wally Skalij/Los Angeles Times/Getty Images

A firefighter sprays water at the remains of an apartment complex on December 5.

Mario Tama/Getty Images

The Storm Prediction Center (SPC), which forecasts the risk of wildfires based on anticipated weather conditions, placed more than 9 million Californians in the "extremely critical" category of fire risk on Thursday — a rare designation. Weather forecasters there warned of the likelihood that any fire that ignites to exhibit: "Large fire spread and extreme fire behavior..."

These fires are an illustration of how short-term weather variability, such as a late season Santa Ana wind event, can combine with climate trends to create a potentially precedent-setting extreme event.

California has see-sawed from one extreme to the next, with one of the wettest winters followed by one of the hottest summers since the late 1800s, and a dry spell that has lasted since March. All this comes on the heels of the worst drought on record there, which lasted for five straight years.

A satellite image of the Thomas Fire on December 6.

NASA

"Southern California has remained unusually dry through November and into December this year, extending the high fire risk fueled by the confluence of dry conditions and Autumn winds that are driving the large fires burning in coastal Southern California," said LeRoy Westerling, a scientist researching climate and wildfire at the University of California at Merced.

Research has already indicated a trend toward larger wildfires in parts of the West, due to human-caused climate change. During the next few decades, California is expected to see an increase in wildfire hazards as the state becomes more prone to droughts and heat waves. Some studies have even tied melting sea ice in the Arctic with weather patterns that yield drier than average conditions in the Golden State.

According to Daniel Swain, a climate scientist at UCLA, studies show that the level of fire risk and amount of land burned in wildfires during Santa Ana events "will increase pretty dramatically" as climate change continues. In a series of tweets on Friday, Swain said there is evidence that shows temperatures will increase and relative humidity will decrease during future Santa Ana events.

Also, he said, the fall season in California is expected to become drier in the future, extending fire seasons, as has occurred this year. "2017 provides [an] example of conditions that match these future expectations," Swain said.

A plane drops fire retardant near a home to stop the wind driven Liberty Fire near Los Alamos Road on December 7 in Murrieta.

Gina Ferazzi/Los Angeles Times/Getty Images

Firefighters prepare to battle the Lilac fire in Bonsall on December 7.

Sandy Huffaker/AFP/Getty Images

Firefighters work to save burning houses along Linda Flora Drive in Los Angeles on December 6, 2017.

Kyle Grillot/AFP/Getty Images

Firefighters monitor a section of the Thomas Fire along the 101 freeway on December 7.

Mario Tama/Getty Images

Horses are led from danger on Sunland Blvd. and Wheatland Ave. as the Creek Fire burns on December 5.

Robert Gauthier/Los Angeles Times/Getty Images

A lone tree burns on December 5.

Ronen Tivony/NurPhoto/Getty Images

Firefighters hose down a burning tree as they protect the beach community of Faria Beach on December 7.

MIKE NELSON/EPA-EFE/REX/Shutterstock

15-year old Sebastian Wayman-Galo waters down the area around his home near Ojai on December 7.

MIKE NELSON/EPA-EFE/REX/Shutterstock

The Thomas Fire on December 5.

VENTURA COUNTY FIRE DEPARTMENT/EPA/SHUTTERSTOCK

According to Cal Fire, 14 of the state's top 20 largest wildfires have occurred since the year 2000, potential evidence of an emerging climate change signal.

"Climate change is increasing the variability of precipitation as well as increasing temperatures," Westerling said. "This means that the probability of extremely large, wind-driven fires in California occurring later in the year is increasing."

In other words, we may need to get used to more of these surreal scenes in the future.

Paul and Erica Mattesich embrace before sifting through rubble at their home in Ventura on December 6.

Noah Berger/AP/REX/Shutterstock

Firefighter Ken Williams hits a hot spot on a fire ravaged home along Linda Flora Drive on December 6.

Genaro Molina/Los Angeles Times/Getty Images

John Bain and Brandon Baker take cover from the embers as they try to help stop a fire from burning a stranger's home on December 5.